Ultra high frequency oscillator



l. E. MCUROMTSEFF ET AL' 293959392 ULTRA-HIGH FREQUENCY OSCILLATOR Filed July 18, 1941 ww Nv ATTORNEY Patented Mar. 19, 1946 UNITED STATES PATENT OFFICE ULTRA HIGH FREQUENCY OSCILLATOR Application July 18, 1941, Serial No. 402,960 s claims. (ol. 25o-27.5)

Our invention relates to high frequency apparatus and especially to the type of high frequency apparatus utilizing hollow body resonators.

An object of our invention is to simplify the construction of high frequency oscillators utilizing hollow body resonators.

Another object of the invention is to provide a hollow body resonator having one integral portion acting as a cathode and another integral portion acting as a grid.

Another object of the invention is to provide means for easily adjusting two resonators to oscillate at the same frequency. Other objects and advantages of the invention will be apparent from the following description and drawing in which: A

Fig. 1 is a cross-sectional view through a preferred embodiment of our invention.

Figs. 2 and 3 are views on lines II-II and III-HI respectively of Fig. l.

In Fig. 1, we have disclosed a simplified, easily adjusted and cooled ultra high frequency oscillator composed of two hollow body resonators I and II placed adjacent each other with a short space I2 therebetween. In their preferred form these resonators comprise cylindrical bodies of sheet copper I 3 and I4 having frusto-conical projections I5 and I6 sloping towards each other and terminating in substantially parallel end walls I1 and I8 bounding the intervening space I2. End wall I 1 is shown as perforate at least in part for passage of electrons therethrough, and consequently the perforate part may be referred to as grid I9 for resonator I0. End wall IB similarly provides a grid 20 as part thereof for the entrance of electrons into the resonator I I.

The space I2 is field free of radio or microwave frequencies but has a high acceleration direct current field as we apply a voltage of the order of 15,000 volts to the resonator and preferably keep the resonator I0 at ground potential.

Projecting within the rst cylindrical body I3 is a smaller cylindrical tubeA 2| of copper terminating closely adjacent to the end wall I1 of the frusto-conical projection I5. This tubemember 2| has its inner end closed by aplate 22 preferably coated on its outer surface toward grid I3 with an electron-emitting material such as barium, strontium, and calcium oxide, thereby constituting said plate a cathode. The grids I0 and 20 are of refractory material such as tantalum, tungsten, molybdenum or graphite and with the perforations of one aligned with perforations of the other so as to intercept a minimum of electrons.

The oxide coating on the plate 22 may be in isletsfcgr# responding in alignment with the openings in the grids. The space between the cylindrical side I3 of this resonator I0 and the tube member 2| is closed by a flexible sheet or diaphragm 23 joined, as by silver solder, at 24 to the outer cylindrical surface I3 and also silver soldered at 25 to the tubular member 2|. This flexible sheet 23 has corrugatlons 25 therein in order to move easily with the adjustment of the position of the tubular member 2 I.,

Within the tubular member 2| and closely adj acent the electron-emitting plate or cathode 22, is a heater 21 with conductors 2B passing through a press 29 to the exterior of the device. The press 29 is sealed into a ring 30 of iron-nickel-cobalt alloy, preferably that sold under the trade name of Kovar, and this Kovar is preferably welded to a ring 3| of steel, that is preferably silver soldered to the inner cylindrical surface of the end and 35, with the outer ring 34 bearing against` the cap 33, and the inner ring 36 secured to a shaft 31 extending to an adjusting handle 33. The shaft 31 and adjusting handle 38 have a central opening therethrough for the heater connections 28. A.Yskeleton cylindrical casing is attached to the cylindrical edge I3 of the resonator I0 and encloses the exterior portion of the tube member 2| and the ball bearing adjustment; The skeleton casing comprises a ring 4| and two arms IIE and II1 supporting an arm 42 extending across the diameter thereof, to provide a screw threaded fulcrum for the shaft 31. The position of the'electron-emitting plate 22 in regard to the 2 grid I9 at the end wall |1 of the first resonator It is adjusted by the handle 38 acting throughv the shaft 31, ball bearing arrangement 34, 35 and 35, steel ring 32 and tubular member 2|. We preferably cover the outer portion of the tubular member 2| with copper fins 43.

Projecting within the cylindrical body I 4 of the second resonator I I is a copper cylinder or collector having its inner edge 5I closely adjacent the grid 20 in the frustrum end wall I8. This copper cylinder has an opening 52 therein which is preferably of considerable diameter at the beginning of the opening 53 and then gradually tapers into a gentle, conical slope 54 to a gently curved bottom 55. In the first part of this opening at` 53 are placed a grid 56 and preferably two or more grids, such as 51 and 58 illustrated. These grids may take the form disclosed in Fig. 2 in which U-shaped members E are having a long leg 0| extending almost to the axis of the opening, and the other leg 62 shortened to occupy the space intermediate the long leg Sl'of this particular grid member, and the long leg of the next grid member B0. The annular positions of these long legs of the three grids are preferably oriented a few degrees such as six degrees fromone-another vto prevent electrons, either primary or secondary, from passing from the opening 52 back into the resonator II. A flexible copper sheet 65 with grooves or corrugations 66 is joined,'asbysilver soldering, to the outer cylindrical edge I4 at 68 and also is preferably silver soldered at fES tothe outer surface of the copper cylinder 155B. f''h'ecopper cylinder at its exterior "end V'I0 Ahas 'secured thereto, a cap 'II enclosing an outer ring "|2fball closes the outer end of the Kovar" eyelet, except for the loops |03 and |04 passing therethrough to terminate in exterior loops |08 and |09, secured at its other end to the eyelets |06. Intermediate Athe exterior loops |08 and |09 is a concentric #and the planes of the two pairs of loops |03, ||2

bearings I3 and inner ring '|41toa1shaft 15.` This construction is similar to that of 34, 35 and 36 at the other end of the casing. A skeleton housing -16 hasta cylindrical ring T'I thatfis attachedto the `oylindricaledge of the second resonator |f|, This skeleton housing may be merely a-couple of arms |20, -|2| 'extending from diametric opposite porztions ofthe ring 'Il for supporting-an-arm Ia-'extending thereacross, similar to the arm'42.to provide a fulcrum for the screw threaded shaft 15. yAnadjusting handle 'i9 is securedonthe shaft l5, where it projects from the casing 178. The adjusting handle 19 moves the cylindrical copper member or collector 50, and this adjusts the'po- :sition of the rstgrid-SS in 4relationstothe sgrid :Zllin the end wall of the'frusto-conical projection 'of the resonator -I I. The cylindrical'copper memlbertll, Vwhere it-emerges from the resonator Il, Llspreferably surrounded by ns 80, and these-may fbe annular fins bound by spacing rings 8| tothe outer surface of this copper cylinder 50. kThe skeleton housing 'IS `permits adequate coolingof the nsll'by a fan or other means.

The'space'between'the two resonators-maybe vperipllerally'enclosed in any desired manner, and .we havedisclosed a particular-advantageous form 'inwhich two rings 90 and 9| slightly largervthan -the diameter of the frustrum ofthe cones have 'one edge 92 and ila-respectivelyshaped'to fit-the .conical :sloped sides I and I6. These Arings are joinedas by soldering, to the conicalisides 'I5 and 16." U-'shaped members 94 and SSpreferablyof iir'on-nickel-cobalt alloy soldunderthe-trade name fof Kovar, have one of their-edges A96 and 0|,re

fspectively, soldered to fa surface of `the-:rings and 9 I, and 'have vtheirouter edges '98'and S9, .re- Espectively cem'entedinto theedges cfa doughnutshaped glasscasing |00. This doughnut-shaped L glass `casing has a tubulation `|0|,'whereby the fspace andthe interior'of both the `4resonators I0 and II, 'canlbe evacuated.` This glasscasing'permitsthehigher voltage ofthe order of-l.0-,000 volts orfmore or less to be'applied to the second resona'tor I I above that applied to thefirstgresonator.

'In'order to provide a feed-back arrangement to adjust the oscillations of the ftwo resonators in both phase and amplitude,'we provide preferably the feed-back arrangement |02 "illustrated, although other types maybe utilized. This .feedback arrangement preferably comprises :interior lc'ops `|03 and l|34 in the two resonators e|0and lil, respectively. One end ofthe loop 4is secured through openings |05 inthe leasing and "axially through a sleeve '|05 'of 'the lironenickel--icobalt Aaliloy sold Vunder the trade name of "'Kovar, which and |09, |13, can be adjusted to provide control of the amplitude and phase of the oscillations in tlietwofhollow body resonators i0 and Il. The outputof'ithehollow body resonator I may be takenlff 'offth'e loop |09 by a similar loop I4 connected tofa concentric transmission line H5. If dcsiredfhoweverfa separate output arrangement similar to the feed-back loops |84 and |09, may be located'on another portion of the resonator l to provide an output to feed the loop H4 and transmission line'IlE. 'If desired, additional loopsmay be appliedto 'either or both resonators to feed in oscillations, preferably at microwave frequencies, tothe resonators,

In operation electrons will'be released from the 4plate or cathode 22 by the action of the heat from the heater wire 2l'. The hollow body resonator l0 will be adjusted to resonate, preferably at microwave frequency, in relationship to the hollow body 1resonator bythe feed-back arrangement |02. These oscillations of the-hollow body I0 will produce a varying polarity at opposite 4portions of the casing. The vplate`22 with one swing of the oscillations will be-a negative polarity and will act as a cathode. End wall at the same instant will bepositive .in regard to the oscillation swing, and this will permitthe electrons to pass rthrough the ,grid -I-9 into the space l2. This space l2 is leldopposite swing of the .oscillations making the grid fili-negative vand the plate 22 positive, The high D. Cfeld -from .theresonator II WillpulltheS electrons through lthe space l2 in bunches .and the electrons will then enter through grid 20 in the .end `wall IBstill hunched. The transmissionline l H242 is-adjustedso .that these electrons `enter the `resonator 4in .opposition toftheeld and, will give .up .theirlcnergy or .alargeportion ofit to the resonator I|. The electrons will pass through "the variousgrids .50, `51 and .58, Vand will he scattered along the gently tapered side 54 of the opening ,52. lThis scattering will prevent any local overheating of the interior surface of the copper cylinderll A'target, preferably of tungsten, may re- :place the collector 50.

It will be noted that the hollow body resonator I0 `is an integral operating unit and yet 'has kone 4portion thereof namely the plate 22, acting as .a cathode, 'and another integral portion, namely a partofend wall |1, acting as Aa grid. This construction eliminates the separate provision of cathode and .grid which were heretofore thought necessary.

-It will be alsonotcdthatthe constructionillustrated, provides a ready `means for replacingthe ^heater wire -21 which is .one of the first elements ,that .may need tto :be replaced, and that 'this `can 'be done :without disturbing 4the vacuum of .the hollow body :fresonater l0. The loosening of the '75 T42 ffrom'the cylindrical casing,r 40, and the unscrewing of the ring 3l from the inner surface of the tubular member 2| will remove the heater wire from the inner portion of the tubularmember 2l for repair or replacement.

While we have disclosed a preferred embodiment of our invention, it is apparent that many modifications may be made therein and, accordingly, we desire only such limitations to be imposed upon our invention as is necessitated by the spirit and scope of the following claims.

We claim:

1. A hollow body resonator comprising a metal casing having at its rear end a flexible metal sheet, a metal tubular member projecting through said sheet, an electron emitting plate at the end of said tubular member, the forward end wall of said casing opposite said plate having an opening for the passage of electrons therethrough, and the side wall of said casing being a rigid metallic body of revolution.

2. A hollow body resonator comprising a metal casing having on one side a ilexible metal sheet, a metal tubular member projecting through said sheet, an electron emitting plate at the end of said tubular member, the wall of said casing opposite said plate having an opening for the passage of electrons therethrough, a press of insulation within said tubular member, means sealed to said press and attached to said tubular member enclosing a space therein, a heater in said space and leads for said heater sealed through said press.

3. A hollow body resonator comprising a metal wall having an opening therethrough, a metal block having one face parallel with said opening, said metal block having an electron receiving cavity in said face and a iiexible metal sheet interconnecting said block and said wall.

4. A hollow body resonator comprising a metal wall having an opening therethrough, a metal block having one face parallel with said opening, said metal block having an electron receiving cavity in said face and a flexible metal sheet interconnecting said block and said wall at an intermediate portion of said block, the outer portion of said block having iins attached thereto.

5. A hollow body resonator comprising a metal wall having an opening therethrough, a metal block having one face parallel with said opening, said metal block having an electron receiving cavity in said face and a flexible metal sheet interconnecting said block and said wall, a casing connected to said wall and exible metal sheet and adjusting means connected to said block and based on said casing for positioning the face of said block in relation to said opening.

6. A hollow body resonator comprising a metall wall having an opening therethrough, an electron emitting plate parallel to the opening in said metal wall and a exible metal sheet interconnecting said plate and said metal wall, a casing connected to said wall and flexible metal sheet and adjusting means connected to said plate for positioning the plate in relation to saidfopening.i

body of revolution connected to said forward end wall and to said flexible rear end wall, the severalsaid walls and emitting plate thereby forming a hollow resonant body, and adjusting means connected to said tubular member and to said side wall for positioning the plate in relation to said opening,

8. An electronic device comprising two resonators having spaced frusto-conical portions extending toward each other, the two ends toward each other of said frusto-conical portions having two ends parallel to and toward each other and having openings therethrough whereby said ends constitute grids as parts of the walls of the resonators, the grid of one frusto-conical portion giving entry to one resonator and the grid of the other frusto-conical portion giving entry to the other resonator, means enclosing vacuum tight the space between sai-d two ends, said means comprising insulation electrically separating the resonators, means 'forming part of the wall of one resonator and constituting a cathode, and means forming part of the wall of the other resonator and constituting a collector, said cathode and collector means being opposite each other with said two grids therebetween,

ILIA E. M OUROMTSEFF. GEORGE M. DINNICK.

D31 s c L A lgMgEjR 2,396,802.Ilia E. Mouromtse', Montclair, and George M. Dt'rmclc, Bloomfield, N.

J. ULTRA HIGH FREQUENCY OscILLAToR. Patent dated Mar. 19, 1946.

Disclaimer filed Sept. 25, 1947, by the assignee, Westinghouse Electric Corporation.

Hereby enters this disclaimer to claim 3 in said specification.

[Ucz'al Gazette October 28, 1.947.] 

